In many industrial belt conveyor applications there exists a constant problem in connection with cleanliness and corrosion. Thus, when corrosive materials, food products or chemicals are being conveyed by a belt-type of conveyor, the conveyor assembly support structure or frame must be constantly or periodically supervised to insure that debris, contaminants and other undesirable particles, fluids and the like do not buildup, become trapped or accumulate upon the conveyor support structure. Such buildups can damage the conveyor frame through corrosion or can contaminate the materials being conveyed on the conveyor belt, or both.
Accordingly, it is not uncommon for considerable effort to be directed toward conveyor maintenance in the form of cleaning the belt supporting frame of a conveyor assembly. While periodic cleaning can be of substantial assistance, the basic construction of the conveyor assembly support structure should be one which is inherently "clean," that is, free of horizontal and other surfaces which will trap debris or cause the buildup of contaminants.
Some limited effort has been previously undertaken to provide conveyor frame systems which are relatively free of debris trapping surfaces. Perhaps the most commonly employed approach is to employ square tubular beams which are oriented so that all of their side walls extend along diagonals. U.S. Pat. No. 3,796,503 is typical of a conveyor support system which is so constructed.
The problem with this approach is that it is very difficult to connect together cross members and support posts to a beam oriented as shown in U.S. Pat. No. 3,796,505. The "solution" of this patent is relatively complex and includes upwardly facing U-shaped members which are certain to trap contaminants.
Another approach is to employ cylindrical support beams under the conveyor. This type of system is illustrated in U.S. Pat. No. 3,327,838. It similarly presents a relatively complex problem with respect to coupling other beams and frame elements to the cylindrical beams.
Beams formed from angle members having the apex of the two legs pointing upwardly have also been employed as conveyor support frames. Typical of this approach are U.S. Pat. Nos. 3,259,227 and 1,838,190 and to some extent U.S. Pat. No. 4,032,002. Again, there are substantial connection or coupling problems in attempting to build a conveyor frame or support structure from angle members, and these prior support systems usually resort to a construction in which the angle members are in turn supported on horizontally oriented upwardly facing surfaces that will act as sites for debris buildup.
Still another approach to the construction of a conveyor support frame is shown in U.S. Pat. No. 2,592,831.